A brief description of the different pancreatic cystic neoplasms and the pseudocyst, including, eidemiology, classification, risk of malignancy, histology, imaging techniques for diagnosis and treatment.
11. Female – middle age 30 – 50 years.
Body or tail of the pancreas 90%.
Presentation:
Abdominal discomfort.
Recurrent Pancreatitis.
Gastric outlet obstruction
Classification:
Adenomas 75%.
Borderline tumors
Carcinoma.
Mucinous Cystic Neoplasm
12. Mucinous Cystic Neoplasm
Characteristics:
Round thick walled cysts, septate.
There is no communication with the
pancreatic ducts.
Subepithelial ovarian-like stroma.
Spindle cells with scant cytoplasm
Small clusters of leutinized cells.
There is association with KRAS
mutation.
16. Surgical resection if any of the following:
> 3 cm.
Main duct dilation
Mural nodule.
Candidates.
Observation if no candidate with small tumors.
Prognosis:
Poor if Invasive disease.
Follow up:
Non invasive: Annually the first years.
Invasive:
Every 4 month the first 2 years.
Biannually until year 5.
Mucinous Cystic Neoplasm: Treatment
17. 25% of the pancreatic cystic Neoplasm.
Male = Female 50 – 70 years.
Head > Body
Presentation:
Abdominal pain.
Pancreatitis.
Weight loss.
Jaundice.
New onset diabetes.
Characteristics:
Main duct dilation.
Papillary projections
Excessive mucin production.
Intraductal Papillary Mucinous Neoplasm.
18. Genetics:
Mutations in K-Ras, CDKN-2a, RNF 43,
Types:
According to the affected duct:
Main duct type.
Invasion 57 – 92 %.
Branch duct type.
Invasion 6 – 46%
According to the dysplasia:
Adenoma.
Borderline.
Carcinoma in situ.
Frankly invasive.
19. Contrast enhanced CT characteristics:
Main pancreatic or duct dilation.
Involvement of any part of the pancreas or
the whole pancreas.
Continuity of cyst with ductal system.
Irregular and poorly demarcated.
Surgical Treatment:
Imaging suggesting malignancy.
Partial Pancreatectomy with Frozen section
analysis.
Follow up: Annually.
24. Female 50 – 70 years old.
Asymptomatic.
Evenly distributed over the pancreas.
Characteristics:
Lining of stratified squamous epithelium.
Surrounding of lymphoid tissue.
Filled by Keratin and cholesterol.
CT:
Multi or unilocular cyst.
Encapsulated
Lymphoepithelial Cyst
MRI:
Hyperintense signal in T1.
Hypointense in T2.
FNA:
Cytology:
Squamous cells and keratin debris.
Cholesterol crystals.
Treatment:
Observation.
Surgery only in equivocal diagnose.
25. Pseudocyst.
Localized fluid collection.
Presented after pancreatitis.
Male > Female.
Fibrous wall and granulation tissue.
Presentation:
Abdominal pain.
Jaundice.
Palpable mass.
GI obstruction.
Infection.
Peritonitis.
30. References:
Katz MH, Mortesson MM, Wang H, et al. Diagnosis and Management of Cystic
Neoplasms of the Pancreas: An Evidence-Based Approach. J Am Coll Surg. 2008
Jul;207(1):106-20.
UpToDate:
Classification of pancreatic cysts.
Pancreatic cystic neoplasms: Clinical manifestations, diagnosis, and
management.
Intraductal papillary mucinous neoplasm of the pancreas (IPMN):
Pathophysiology and clinical manifestations.
Imaging in Mucinous Cystic Neoplasms of the Pancreas.
http://emedicine.medscape.com/article/371197-overview
Pancreatic Pseudocyst Imaging
http://emedicine.medscape.com/article/373117-overview#a1
Notes de l'éditeur
Pancreatic cystic neoplasm are an heterogeneous group of cystic lesions with different histology and pathology, with a different natural history, they can be symptomatic or asymptomatic, and they are usually an incidental finding in 2% of people who get a CT scan or and MRI of the abdomen.
Our main concern is the potential association with malignancy in 0.1% at moment of diagnosis, also, there are some criteria that makes us think about the possibility of malignancy such as cyst bigger than 3 centimeters, a solid component, main pancreatic duct dilation .
There are several types of pancreatic cysts, There are divided in neoplastic and non-neoplastic, the neoplastic can be divided in Serous and mucinous, the solid pseudo papillary tumor and lymph epithelial cyst, there are also come cystic presentation of some solid tumor like ductal adenocarcinoma, the neuroendocrine tumors and Acinar cell carcinoma,.
The non neoplastic cysts are divided in the True Cyst, which are benign cyst with cuboidal epithelial lining.
Retention cysts are small dilated pancreatic duct side branches rising due to obstruction.
Mucinous non neoplastic cysts: Similar to the mucinous neoplastic cyst but lacks neoplastic features, like atypia or ductal communication.
Serous cystic tumor represents 1% of the overall exocrine pancreas tumor, and 30% of cystic neoplasm, they come from the pancreatic centroacinar cells It’s usually found in Women from 50 years old to 70, there is no preferred location of the tumor in the pancreas and there is a low risk of malignancy, the cyst adenocarcinoma it’s extremely weird, they have the same appearance as the Cystadenoma, and the only difference is the metastatic component..
The Clinical presentation is seen usually in cysts bigger than 4 cm, 50% are incidental cases so they don't have symptoms, other patients may complaint of Epigastric pain, Abdominal fullness and weight loss.
Histology of the cyst include a glycogen rich cuboidal epithelium which is PAS positive, and it’s usually Polycystic with multiple small cysts. In the cases that is oligocystic, it can be mistaken for other cysts.
The image shows a Cystadenoma, with multiple small cysts and a Stellate scar, a common finding that can be seen on CT.
Here we can see two pictures that show the glycogen content and the cuboidal epithelium of the cyst.
Then characteristics on CT includes the Microcysts, the stellate scar AKA as Sunburst calcifications, Septation within the cysts and a Honeycomb appearance.
Doubtful cases might need additional evaluation, including MRCP which can show hiperintense lesion on T2,
Endoscopic ultrasonography with FNA can show scant cellularity on cytology, it can have a bloody appearance, and chemistry show low CEA which distinguishes from mucinous cysts, low amylase, low CA 19-9 although this marker has very low specificity.
The image show a CT of a patient with suspicion of a Serous cystic tumor we can see the multiple microcysts, with the Stellate scar and the honeycomb appearance.
About the treatment of the Serous cysts, if it presents with a classical image or US with FNA, and there is no symptoms, we can follow up every 6-12 month. We should consider resection if > 4, becomes symptomatic, there is no definitive diagnosis of increase the rate of growth.
We can see in this picture how it would see a serous cystic tumor in an endoscopic ultrasound, we can see the multiple cysts involving all the pancreas.
Image 1: Abdominal CT of a 69 Years old F, with chronic abdominal pain, there is a 9 cm in the tail of the pancreas with multiple cysts, septation, honeycomb appearance of a serous cystadenoma.
Image 2: CT scan od a different person, a 56 y/o F with an asymptomatic unilocular cyst of the uncinated process, EU-FNA was indeterminate so they performed a pylorus presenting pancreatodudenectomy, Pathology was consistent with an Oligocystic SCA.
Picture 1: A 68 y/o F, with a 3 year history of abdominal pain. CT show a low density lesion within the pancreatic tail with tiny cysts within it.
Picture 2: The lesion had high intensity on T2 weighted MRI.
This patient was confirmed with Serous Adenocarcinoma. We can see in this patient also an hepatic cyst.
The first mucin producing neoplasm that we are going to talk about today is the Mucinous Cystic neoplasm, I should say that these type of neoplasms are whether premalignant or can potencionally develop malignant cancer.
90% of the cysts are found in the Body or Tail of the Pancreas, the most common symptoms are, abdominal discomfort, nausea, recurrent pancreatitis, and symptoms of Gastric outlet obstruction such as vomit, fullness sensation.
The mucinous neoplasm can be classified in Adenomas, borderline tumors and carcinoma.
We Can see in the picture, multiple big cysts of a mucinous cystic neoplasm, with it’s thick walls and the mucin content.
Characteristic of this kind of neoplasm includes a round, thick walled cyst septate, no communication with the pancreatic duct, this can differentiate this tumor with the IPMN and a subepithelial ovarian like stroma, scant cytoplasm and a small cluster of leutinized cells.
There is association with KRAS mutations in cystic fluid bur this is not really sensitive.
We can see in the picture the lining of the mucinous cells and somewhat the spindle cells of the stroma
Characteristics on the images include a thick cyst Wall, with smooth Sharp boundaries, the cyst des not communicate with the pancreatic ductal system and pancreatic duct dilation
Eggshell calcifications and the ones we already know, > 3 cm and solid component they are all related to malignancy.
Viscous fluid (Gastroenterologist String sign)
CEA: Adenoma > 200 and the presence of CEA > 6000 can be strongly suggestive of Cyst adenocarcinoma,
PET/Scan can also differentiate begin and malignant cyst.
Picture show: 44 y/o F, complaining of postprandial pain, CT was performed and showed a 6 cm thick walled and septate cyst, a Whipple procedure was performed for a presumptive MCN
Enhanced axial CT scans show a large septate mass in the left hypochondrium with rim enhancement and enhancement of the septa. At surgery, a mucinous adenoma was confirmed. Note the smooth external contour typical of a mucinous cystic neoplasm
Contrast-enhanced axial CT scans through the tail of the pancreas show a large, enhancing tumor occupying the left hypochondrium, with cystic and solid components. At surgery, a mucinous carcinoma of the pancreatic tail was confirmed.
Treatment of the MCN includes surgery if > 3 cm, main duct dilation, mural nodules and if the patient is candidate for surgery. Observation is recommended of patients that are not candidate for surgery, especially if with small tumors
Axial and sagittal sonograms through the pancreas show a 1.93-cm cystic mass in the head of the pancreas. At surgery, a mucinous adenoma was confirmed
IPMN accounts for 25 % of the PCN, there is a similar frequency between men and women, usually occurs in people from 50 to 70 years old..
Common symptoms of presentation includes, abdominal pain, weight loss, Jaundice, recurrent pancreatitis and new onset diabetes.
It’s main characteristics includes, excessive mucin production, papillary projections and dilation of the main duct.
The picture show a IPMN seen by endoscope that and a papilla extruding mucus. A very common finding in IPMN.
IPMN can be classified according to the affected duct in the branch duct type and main duct type, the last one carries a less risk of invasive neoplasms.
According to the grade of dysplasia, can be classified in Adenoma, Borderline, Ca in situ and Frankly invasive.
The picture show a CT scan of the abdomen in a patient with IPMN, you can see dilation of the mucinous neoplasm and parenchymal atrophy.
CT characteristics show, duct dilation, involvement of any part of the pancreas, continuity with ductal system, I
Treatment includes partial pancreatoduedenoctomy specially for patients with main duct involvement. with fr4ozen analysis in all cases with good functional status..
The picture shows MRCP, that reveals IPMN, multiple dilated branch ducts and moderate dilated main pancreatic duct.
.
(B) Incidentally identified 2.5-cm cyst in the uncinated process (arrow) in a 73-year-old man undergoing
therapy for prostate cancer. Cyst aspiration did not demonstrate malignant cells. Branch duct IPMN was the favored diagnosis. The patient has been followed closely.
Pancreatic intraductal papillary mucinous tumor (IPMT). Contrast-enhanced axial CT scans through the pancreas show a 5.5-cm cystic tumor in the pancreatic head. Note the upstream, gross dilatation of the pancreatic duct. The accessory pancreatic duct is also dilated.
Poorly describe tumor, common in Young female, characteristics include a large capsulated cyst with hemorrhage, cystic degeneration and calcification,.
Differential dx include NET differences include Accumulation of b catenin protein, Vimentin post and CD10 pos, is negative for chromogranin,
Pancreaticoduodenectomy specimen demonstrating focal hemorrhage and cystic degeneration consistent with a diagnosis
of solid pseudopapillary tumor (SPPT).
Solid and cystic lesions, with some calcification, in an incidentall finding.
Uncommon cyst, that is found in female 50 – 70 yeas old, is usually asymptomatic bur it can present by unspecific symptoms like abdominal pain, the cyst is typically evenly distributed throughout the pancreas, it’s characteristics include a lining of stratified squamous epithelium, surrounded by lymphoid tissue filled by keratin and cholesterol.,
CT: show a multinodular or unilocular cyst that is encapsulated.
MRI: Can show and hyper intense signal in T1 that is hypointenese in T2 due to the content of keratin in the cyst. FNA can show squamous cells and keratin debris with cholesterol crystals.
This type of cyst is benign so even in symptomatic patients is recommended unless the diagnose is equivocal.